Mav,
Try FCOM 4.5.70 page 3 and you'll find a graph and text showing the intercept angle that the autopilot can cope with at various speeds.
It also adds:
Note : ICAO requires loc beam to ensure a normal capture within 10 NM and plus or minus 35 degrees from the course centerline. Some ILS systems just meet the requirement and are subject to false capture outside these limits.
Sorry didn't have any luck posting the picture et al!
